/*
* FLINT PARTICLE SYSTEM
* .....................
* 
* Author: Richard Lord
* Copyright (c) Richard Lord 2008-2011
* http://flintparticles.org
* 
* 
* Licence Agreement
* 
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
* 
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
* 
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/

package org.flintparticles.common.activities;

import org.flintparticles.common.emitters.Emitter;
import org.flintparticles.common.activities.FrameUpdatable;
import org.flintparticles.common.activities.UpdateOnFrame;
import org.flintparticles.common.activities.ActivityBase;

/**
 * The UpdateOnFrame activity is used to call a frameUpdate method of an object 
 * that implements the FrameUpdatable interface. The frameUpdate method is called
 * once every frame.
 * 
 * <p>This activity is most often used to update an action once every frame.
 * Because the update method of an action is called once for every particle, 
 * every frame, there is no obvious point for an action to implement code
 * that should be called once only every frame, irrespective of the number
 * of particles. If the action implements FrameUpdatable and adds an 
 * UpdateOnFrame activity to the emitter in its addedToEmitter method, the
 * frameUpdate method will be called once every frame.</p>
 * 
 * <p>See the Explosion Action for an example of an action that uses this 
 * activity.</p>
 * 
 * @see org.flintparticles.twoD.actions.Explosion
 */
class UpdateOnFrame extends ActivityBase
{
	private var action:FrameUpdatable;
	/**
	 * The constructor creates an UpdateOnFrame activity.
	 * 
	 * @param fu The object that shouldbe updated every frame.
	 */
	public function new( frameUpdatable:FrameUpdatable )
	{
		super();
		action = frameUpdatable;
	}
	
	/**
	 * Calls the frameUpdate method of the FrameUpdatable object associated
	 * with this activity.
	 * 
	 * <p>This method is called by the emitter and need not be called by the 
	 * user</p>
	 * 
	 * @param emitter The Emitter.
	 * @param time The duration of the frame - used for time based updates.
	 * 
	 * @see org.flintparticles.common.actions.Activity#update()
	 */
	override public function update( emitter:Emitter, time:Float ):Void
	{
		action.frameUpdate( emitter, time );
	}
}
